The present invention relates to substrate remounting and system designs for chemical vapor deposition (CVD) systems and CVD synthesis used to synthesize at least one layer or to grow at least one nano-structured material on at least one surface of a flexible substrate, and more particularly, to scalable thin film coating and nano-structured material manufacturing of products such as nanotubes, nanowires, and nanosheets.
Those skilled in the art will recognize that there is an ongoing interest in economical solutions that enable the manufacturing in large volume of higher quality, nano-structured materials (e.g., in tube, fiber or wire format, such as 1-5 mm tall, 10-20 nm thick vertically aligned carbon nanotubes; 100-200 nm thick vertically aligned carbon nanofibers; 10-50 μm long, 50-100 nm thick random or vertically aligned silicon nanowires as can be synthesized by CVD processes on, for example, flexible stainless steel foil).
It will be recognized that the ability to produce higher quantities of higher quality nano-structured materials at lower production cost per usable coated area is desirable, for example, to unlock many of the potential benefits that nano-structured material and CVD surface modification research has created over the last 20 years. In this regard, the lack of related economical production solutions has hindered commercialization efforts.
US patent application 2014/0113074 A1 is directed to a graphene manufacturing process utilizing a Cu foil substrate roll, which together with a gas porous material layer, is rolled up into an Archimedes spiral roll. However, the gas porous material interferes with local surface processing, and hinders the growth of undisturbed, higher quality nano-structured materials like carbon nanotubes and silicon nanowires.
Nearly all prior art has remained focused on roll-to-roll CVD systems for providing solutions for increased productivity and lower large area production costs of CVD processed flexible substrates. Such an approach, however, necessarily requires that the length and/or size of the CVD reactor chamber be increased. Additionally, the processing conditions developed with batch process CVD systems used for research and development (R&D) are typically not directly portable to roll-to-roll CVD systems, which then typically requires multiple generations of pilot system development prior to scale up to a production roll-to-roll CVD system. This thus increases the capital cost, development risk and commercialization time frame of roll-to-roll CVD projects, often putting it out of reach for many smaller/startup corporations. As a result, the scale up of large area CVD processed films and/or nano-structured material covered flat substrates has, in the past, only been implemented commercially on a selective basis for high volume applications. It will be appreciated that this type of a project risk typically could be afforded only by large corporations with preexisting product sales channels.
There is therefore a need in the art for the ability to transfer processes for nano-structured materials or thin film surface modifications utilizing flexible substrates and developed on batch process CVD systems to volume production with batch process CVD system solutions that are less risky and costly to scale up. In addition, it is desirable that such batch process solutions allow processing of one or more rolls of flexible substrates. Further, it is desirable that such a system solution be adaptable to a range of CVD processing needs, without costly hardware changes or upgrades.